关于回收废混凝土粉 (RWCP) 在混凝土上的性能的实验研究
Shuai Wang1,2, Aixun Wang1, Xudong Fu2
1Wuhan Construction Group Co., Ltd., Wuhan 430056, China.
Materials (Basel, Switzerland)
|November 9, 2024
概括
回收废混凝土粉 (RWCP) 显示出混凝土制备的潜力. 最佳研磨提高了其活性,提高了流动性,但在取代高炉渣时降低了早期的强度. 用RWCP取代飞灰可以提高混凝土的强度和不透性.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 可持续建筑 可持续建筑
背景情况:
- 废混凝土在中国城市发展中构成了重大固体废物挑战.
- 利用回收废混凝土粉 (RWCP) 为节约资源和改善环境提供了一个可持续的解决方案.
研究的目的:
- 调查机械研磨时间对RWCP颗粒大小分布和活性的影响.
- 分析RWCP对混凝土机械性能,可加工性和不透性的影响.
- 评估混凝土的微观结构和相位变化,其中包括RWCP.
主要方法:
- 机械研磨废混凝土以生产RWCP.
- 描述RWCP活动和颗粒大小分布.
- 混凝土测试包括不受限制的压力强度 (UCS),倾斜,电流和离子透阻力.
- 使用X射线衍射 (XRD) 和扫描电子显微镜 (SEM) 分析混凝土相位和微观结构.
主要成果:
- RWCP主要由石英,吉斯蒙丁,C2S,癌和波特兰组成.
- 通过45分钟的球磨,实现了最佳的RWCP活动 (44.41%).
- RWCP提高了混凝土的流动性,并减少了初始设置时间.
- 用RWCP取代高炉渣,导致早期强度和不透性降低.
- 用RWCP取代飞灰 (FA) 增加了混凝土的强度,当FA完全被取代时,混凝土的28天强度显著增加.
- 适当的RWCP替代FA提高了混凝土的不透性;过度的替代降低了它.
结论:
- RWCP,特别是通过机械研磨进行优化时,显示出大规模混凝土应用的巨大潜力.
- 用RWCP替代飞等补充水泥材料的战略性替代可以提高混凝土性能.
- 对最佳替代水平的进一步研究是有必要的,以平衡性能好处和潜在缺点.
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